Use portable shell code to follow symlinks.

From: Aaron Kimball <aaron@cloudera.com>

git-svn-id: https://svn.apache.org/repos/asf/incubator/sqoop/trunk@1149911 13f79535-47bb-0310-9956-ffa450edef68

bin/configure-sqoop

@@ -18,9 +18,12 @@
 # This is sourced in by bin/sqoop to set environment variables prior to
 # invoking Hadoop.
 
-prgm=`readlink -f $0`
-bin=`dirname ${prgm}`
-bin=`cd ${bin} && pwd`
+bin="$1"
+
+if [ -z "${bin}" ]; then
+  bin=`dirname $0`
+  bin=`cd ${bin} && pwd`
+fi
 
 if [ -z "$SQOOP_HOME" ]; then
   export SQOOP_HOME=${bin}/..

bin/sqoop

@@ -15,10 +15,85 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-prgm=`readlink -f $0`
+
+follow_one() {
+  # Resolve symlinks and relative path components along a path.  This requires
+  # its argument to be an absolute path.  This does not recursively re-resolve
+  # symlinks; if that is required, use the 'follow' method.
+
+  target=$1
+  OIFS=$IFS
+  IFS='/'
+
+  # Taking each dir component along the way, build up a new target directory,
+  # resolving '.', '..', and symlinks.
+  newtarget=''
+  for part in ${target}; do
+    if [ -z "${part}" ]; then
+      continue # Empty dir part. 'foo//bar'
+    elif [ "." == "${part}" ]; then
+      continue # Nothing special to do for '.'
+    elif  [ ".." == "${part}" ]; then
+      IFS=$OIFS
+      newtarget=`dirname ${newtarget}` # pop a component.
+    elif [ -h "${newtarget}/${part}" ]; then
+      IFS=$OIFS
+      link=`readlink ${newtarget}/${part}`
+      # links can be relative or absolute. Relative ones get appended to
+      # newtarget; absolute ones replace it.
+      if [ "${link:0:1}" != "/"  ]; then
+        newtarget="${newtarget}/${link}" # relative
+      else
+        newtarget="${link}" # absolute
+      fi
+    else # Regular file component.
+      newtarget="${newtarget}/${part}"
+    fi
+    IFS='/'
+  done
+
+  IFS=$OIFS
+  echo $newtarget
+}
+
+follow() {
+  # Portable 'readlink -f' function to follow a file's links to the final
+  # target.  Calls follow_one recursively til we're finished tracing symlinks.
+
+  target=$1
+  depth=$2
+
+  if [ -z "$depth" ]; then
+    depth=0
+  elif [ "$depth" == "1000" ]; then
+    # Don't recurse indefinitely; we've probably hit a symlink cycle.
+    # Just bail out here.
+    echo $target
+    return 1
+  fi
+
+  # Canonicalize the target to be an absolute path.
+  targetdir=`dirname ${target}`
+  targetdir=`cd ${targetdir} && pwd`
+  target=${targetdir}/`basename ${target}`
+
+  # Use follow_one to resolve links. Test that we get the same result twice,
+  # to terminate iteration.
+  first=`follow_one ${target}`
+  second=`follow_one ${first}`
+  if [ "${first}" == "${second}" ]; then
+    # We're done.
+    echo "${second}"
+  else
+    # Need to continue resolving links.
+    echo `follow ${second} $(( $depth + 1 ))`
+  fi
+}
+
+prgm=`follow $0`
 bin=`dirname ${prgm}`
 bin=`cd ${bin} && pwd`
 
-source ${bin}/configure-sqoop
+source ${bin}/configure-sqoop "${bin}"
 ${HADOOP_HOME}/bin/hadoop jar ${SQOOP_JAR} \
     com.cloudera.sqoop.Sqoop "$@"

src/scripts/run-perftest.sh

@@ -30,7 +30,7 @@ bin=`cd ${bin} && pwd`
 SQOOP_HOME="${bin}/../../"
 
 # Set up environment and classpath
-source ${SQOOP_HOME}/bin/configure-sqoop
+source ${SQOOP_HOME}/bin/configure-sqoop "${bin}"
 
 PERFTEST_CLASSES=${SQOOP_HOME}/build/perftest/classes